Material for use with a capacitive touch screen

ABSTRACT

A modified material for use with a capacitive touch screen is described. The modified material comprises a material impregnated with a composition comprising either a non-metallic and/or a metallic conductive agent with a binder. A variety of materials are contemplated, including, but not limited to leather. Also described is an apparatus and method of providing a conductive glove is disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Patent Application Ser. Nos.61/217,653, filed Jun. 3, 2009, 61/240,934, filed Sep. 9, 2009,61/266,840, filed Dec. 4, 2009, and 61/285,468, filed Dec. 10, 2009, thedisclosures of which are incorporated herein by reference in theirentirety.

FIELD OF THE EMBODIMENTS

The described embodiments relate generally to a modified material thatis capable of operating a capacitive touch screen. The material isimpregnated with a composition comprising either a metallic or anon-metallic conductive agent and a binder. More particularly, thedescribed embodiments relate to a conductive glove or a glove that iscapable of coupling to a capacitive touch screen.

BACKGROUND

In recent years the development and manufacture of electronic devicesusing a touch screen as the human input interface has grownexponentially. Multi-touch mobile phones and handheld devices arebecoming ever popular. The new multi-touch capacitive touch screen isquickly becoming the dominant type of technology used by manufacturersof these devices, as can be seen with the success of Apple Computer'siPhone, iTouch, and iPad. Many other manufacturers have also adopted theuse of multi-touch capacitive touch screens as to enable human interfacewithout need of a stylus, keyboard or mouse. Touch screens also play aprominent role in the design of digital appliances such as the personaldigital assistant (PDA), satellite navigation devices, mobile phones,video games, automatic teller machines (ATMs) and even light switches.However, the user cannot interface with these multi-touch devices, asintended, when the user of the device is wearing gloves or is otherwiseunable to touch the screen with their skin. This can particularly be aproblem in, for example, northern or southern hemisphere countries whenthe weather is colder. However, even for short periods of cold weather,like during skiing, the operation of touch mobile devices is a problem.Additionally, certain occupations require or suggest the use of glovesto protect the hands from injuries, such as contractors, productdelivery drivers, military and public safety personnel. There are alsocertain transportation and recreational activities where the use ofgloves might be used, such as, golfers, motorcycle riders and gardeners,who desire to operate their touch devices.

A popular form of the touch device includes a touch screen whichoperates in a capacitive mode. For the capacitive system, a layer thatstores electrical charge is placed on the glass panel of the monitor ofthe touch screen devices. This is a form of capacitive coupling betweenthe user and the capacitive touch screen. This decrease is measured bycircuits located at each corner of the monitor. A processor of the touchscreen device calculates, from the relative differences in charge ateach corner, exactly where the touch event took place and then relaysthat information to the touch-screen driver software.

The problem surrounds the fact that capacitive touch screens rely uponan electrical response (transfer of charge or capacitive coupling) fromor to the user's body. Gloves and prosthetic devices, unsurprisingly,prevent the electrical charge from passing through to the screen.Therefore, one is required to remove a glove whenever activating thedevice, like making a phone call, sending a text a message, checkingemail, or operating any other touch screen device.

There is a need for a material that provides a user with the typicalbenefits provided by gloves, but additionally allows the user to operatea touch-screen device without having to remove the glove or otherwiseput their skin in contact with the touch screen. More particularly toenable the material, itself, to capacitively couple with touch screendevices by use of an electrostatic discharge enabling interaction withsuch devices without the need of human skin contact for such capacitivecoupling. Such a material would allow someone who might have lost afinger, hand or limb and has a prosthetic in its place to use touchscreen devices as modern prosthetics are not designed to enablecapacitive coupling to these capacitive touch screens.

Various attempts have been made to produce hand protection that allowsinteraction of such devices without removing the gloves. None of thesesolutions provide sufficient protection from chemicals, weather or otherpotentially harmful situations, nor allow use of the ten fingergesturing capabilities of the newer touch screens.

Accordingly, there is a need for a new type of performance leather thatreplicates the human touch, without the actually need to capacitivelycouple to the human body, in order to enable the use of these deviceswithout having to remove the glove.

SUMMARY

In order to properly operate a capacitive touch screen device withgloves on or without the ability to contact human skin and without theuse of a device, such as a stylus or other embodiment specificallycreated for this purpose, the glove or other material must provideenough electrical capacity to operate the touch screen. Materials ofthis invention provide the requisite electrical capacity to perform insuch a manner, thereby allowing for operation of the touch screen absenthuman conductive coupling to the device.

In one embodiment, the invention is directed to a modified materialcomprising a material where at least a portion of which is impregnatedwith a composition comprising a non-metallic electrically conductiveagent and a binder at a sufficient concentration of the conductive agentto provide electrical conductivity in that portion of the impregnatedmaterial. In another embodiment, the material is impregnated in at leasta portion thereof with a metallic electrically conductive agent. Inanother embodiment, the material is textile, leather, non-wovenmaterial, or a leather-like material. In another embodiment, thematerial has a volume resistivity of less than about 1.0×10⁶ Ohm-cm orless than about 1.0×10⁵ Ohm-cm, or less than about 1.0×10⁴ Ohm-cm, orless than about 1.0×10³ Ohm-cm or less than about 1.0×10² Ohm-cm.

The invention is also directed to a method of operating a capacitivetouch screen by placing the modified material of the invention inproximity to the touch screen in a manner that allows for operation ofthe touch screen.

In one embodiment, a glove comprises the modified material describedabove. In another embodiment, a user wearing the glove may operate acapacitive touch screen. In some embodiments, the glove is comprised ofthe modified material such that the user can take advantage of “TenTouch” touch screen devices, which utilize all ten fingers being incontact with the screen at the same time in order to solicit a specificresponse from the multi-touch touch screen devices.

Also provided is a leather product, either black or colored, having avolume resistivity of less than about 1.0×10⁶ Ohm-cm. In someembodiments, the volume resistivity is from about 1.0×10³ Ohm-cm toabout 1.0×10⁴ Ohm-cm.

One additional embodiment includes a conductive glove. The conductiveglove optionally includes a liner, wherein the liner is less than 1 mmthick and/or has a volume resistivity of less than 1.0×10⁶ Ohm-cm. Theconductive glove further includes an electrically conductive thermalinsulator layer adjacent to the liner, and optionally an outer shelladjacent to the electrically conductive insulating layer, wherein theouter shell is optionally less than 1 mm thick and/or has a volumeresistivity of less than 1.0×10⁶ Ohm-cm.

Another embodiment includes a further iteration of a conductive glove.In this iteration, the conductive glove includes an outer shell. Theouter shell includes at least one conductive channel, wherein at leastone the conductive channel extends from an inner surface of the outershell to an outer surface of the outer shell, and the conductive channelhas a volume resistivity of less than 1.0×10⁶ Ohm-cm.

In one embodiment, at least one the fingers or the pad of the fingers ofthe glove are impregnated with a non-metallic or metallic electricallyconductive agent and a binder at a sufficient concentration of theconductive agent to provide electrical conductivity in to the fingers ofthe glove.

In another embodiment, the entirety of the glove is impregnated with anon-metallic or metallic electrically conductive agent and a binder at asufficient concentration of the conductive agent to provide electricalconductivity in to the entirety of the glove.

Other aspects and advantages of the described embodiments will becomeapparent from the following detailed description, taken in conjunctionwith the accompanying drawings, illustrating by way of example theprinciples of the described embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cross-section of an embodiment of an electricallyconductive glove.

FIG. 2 shows a cross-section of another embodiment of an electricallyconductive glove.

FIG. 3 shows a cross-section of another embodiment of an electricallyconductive glove.

FIG. 4 shows a cross-section of another embodiment of an electricallyconductive glove.

DETAILED DESCRIPTION

Prior to discussing the invention, all numerical designations, e.g., pH,temperature, time, concentration, and molecular weight, includingranges, are approximations which are varied (+) or (−) by increments of5%. It is to be understood, although not always explicitly stated thatall numerical designations are preceded by the term “about”. It also isto be understood, although not always explicitly stated, that thereagents described herein are merely exemplary and that equivalents ofsuch are known in the art.

It must be noted that as used herein, and in the appended claims, thesingular forms “a,” “an,” and “the” include plural references unless thecontext clearly dictates otherwise.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meanings as commonly understood by one of ordinary skillin the art to which this invention belongs. Although any methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of the present invention, the preferred methods,devices, and materials are now described. All publications cited hereinare incorporated herein by reference in their entirety for the purposeof describing and disclosing the methodologies, reagents, and toolsreported in the publications that might be used in connection with theinvention. Nothing herein is to be construed as an admission that theinvention is not entitled to antedate such disclosure by virtue of priorinvention.

As used herein, the term “comprising” is intended to mean that thecompositions and methods include the recited elements, but do notexclude others. “Consisting essentially of” when used to definecompositions and methods, shall mean excluding other elements of anyessential significance to the combination for the intended use. Thus, acomposition consisting essentially of the elements as defined hereinwould not exclude trace contaminants from the isolation and purificationmethods of the components of the compositions disclosed herein.“Consisting of” shall mean excluding more than trace elements of otheringredients of the compositions of this invention. Embodiments definedby each of these transition terms are within the scope of thisinvention.

Materials

The invention is directed to, in part, a modified material comprising amaterial where at least a portion of which is impregnated with acomposition comprising a non-metallic electrically conductive agent anda binder at a sufficient concentration to provide electricalconductivity in the impregnated material. What is meant by the term“impregnate” is that the material is somehow filled or infused with thecomposition. In some embodiments, the material is coated with theconductive agent without the use of an adhesive layer. In otherembodiments, the composition fills voids or interstices of the material.This can be accomplished in a variety of ways, including but not limitedto spraying, roll coating, screen printing, brushing, sponging, dipping,drying, curing, soaking, rinsing, or combinations of a variety oftreatments and the like. For example, the composition may be applied toa material by spraying and then drying the material with or withoutheat. This is more thoroughly described in the next section.

It is contemplated that the materials of the invention may include, butare not limited to, textiles, leathers, non-woven materials, and aleather-like materials. It is contemplated that the materials of theinvention comprise some voids or interstices to allow for effectiveimpregnation of the conductive agents. These materials may include, butare not limited to, leather, faux leather, suede, faux suede, polymer,wool, cotton, fur, nylon, fleece (including microfleece), fabric, cloth,woven and knitted materials, polyester, nylon, synthetic fabrics,rubber, latex, neoprene and the like.

As used herein the term “conductive agent,” also referred to herein as“electrically conductive” filler material, refers to an agent that iselectrically conductive. In some embodiments, the agent isbiocompatible, meaning it is compatible with human tissue. In certainembodiments, the conductive agent comprises conductive particles and/orconductive fibers. The “non-metallic conductive agents” include, but arenot limited to, carbon black, carbon nanotubes, graphite, PEDOT, andcombinations thereof. In certain embodiments, the conductive agentcomprises carbon fiber chains with at least some of the carbon fiberchains having a length of greater than 100 nanometers. In otherembodiments, the agent is long chain carbon black.

The non-metallic conductive agent may also be a polymer. Representativepolymers include poly(acetylene)s, poly(pyrrole)s, poly(thiophene)s,polyanilines, polythiophenes, poly(p-phenylene sulfide), andpoly(para-phenylene vinylene)s (PPV), polyindole, polypyrene,polycarbazole, polyazulene, polyazepine, poly(fluorene)s, andpolynaphthalene and combinations thereof.

The term “metallic conductive agents” refers to a variety of conductivemetals. Those metals include silver, copper, gold, nickel, aluminum,indium, zinc, tin, tantalum, magnesium, sodium, beryllium, barium,cadmium, calcium, rubidium, cesium, lithium, molybdenum, cobalt,uranium, chromium, manganese, iron, platinum, tungsten, osmium,titanium, iridium, ruthenium, nickel, rhodium, palladium, steel,thallium, lead, niobium, vanadium, arsenic, antimony, mercury, bismuth,tellurium and combinations or alloys thereof. In certain embodiments,the metallic agent may be selected from the group consisting of silver,copper, gold, nickel, aluminum, indium, zinc, tin, and combinations oralloys thereof.

Whether employing a metallic or non-metallic conductive agent, theconductive agent may serve as a coating to another particle or fiber.For example, silver-coated glass beads and silver-coated fiberglass areuseful in materials of the invention. Further, it is also contemplatedthat a combination of conductive agents may be used. For example,silver-coated glass beads can be used in conjunction with carbon black.

The amount of conductive agent required can be readily determined by oneof skill in the art based on the conductivity of the agent selected. Forexample, it is contemplated that for some conductive agents, themodified material will be comprised of at least about 30% (w/w) ofconductive agent. For example, it is contemplated that for someconductive agents, the modified material will be comprised of at leastabout 5% (w/w) of conductive agent. When selecting the amount ofconductive agent, the desired conductivity should be considered. Forexample, the modified materials of the invention have a volumeresistivity of less than about 1.0×10⁶ ohm-cm or less than about 3.0×10⁵ohm-cm or less than about 1.0×10⁵ ohm-cm or less than about 1.0×10⁴ohm-cm or less than about 1.0×10³ ohm-cm. Further, the modified materialretains similar volume resistivity after any pre-commercializationtreatments, such as stretching, bending, deforming and the like. It isalso contemplated that the materials of the invention retain theirconductivity after being used for about 1 month or longer. It iscontemplated that the modified material of the invention retains itsconductivity for at least about 6 months or at least a year or longer.

In other embodiments, the conductive agent is substantiallyhomogeneously dispersed or suspended with a binder. Any number ofsuitable binders will suffice and can be readily determined by one ofskill in the art based on material on which it is being applied. Thecomposition may also optionally comprise aqueous polyetherpolyurethanes, solvent-borne polyether/polyester, aqueous acrylics,styrene butadiene rubber, nitrocellulose lacquers and water emulsions,cellulose acetate butyrate lacquers and water emulsions, shellac, epoxy,polyvinyl chloride, oils, waxes, silicones, and/or combinations thereof.Additional components include dyes and pigments, ionic additives, pHbalancers, fastness agents, water, adhesion promoters, bonding agents,aromatic polyurethanes, aliphatic polyurethanes, carriers includingresins, binders, cross-linking agents, acrylics, UV protectiveadditives, feel enhancers, and the like.

In certain embodiments the material optionally has any number ofadditional coats, such as for example, a base coat, a midcoat, a colorcoat, and a top or finishing coat. The additional components may be inany number of additional coats just described. Further, the compositioncomprising the conductive agent can be applied in a base coat, amidcoat, a color coat, and/or the top coat. In one embodiment, the topcoat comprises cellulose acetate butyrate. In one embodiment, the basecoat does not contain an adhesive material. In another embodiment, thebase coat comprises carbon black as the conductive agent.

One embodiment of the present invention is directed to a leather whichhas been impregnated with a capacitive material, such as carbon black,that allows the flow of electrons in the form of an electrostaticdischarge in order to operate touch screen devices.

In one embodiment, the present invention provides a process for tanningleather for use in gloves or garments with the unique ability todischarge static electricity, which can be harmful to electronicdevices.

Another embodiment of the present invention is directed to a tannedleather which consists of a collagen based internal fiber matrix, madeup of the grain, corium-grain junction, the corium and a plurality ofcapacitive particles creating a conductive network throughout thematerial, or portions or layers thereof. The capacitive particles, areembedded within the fiber matrix and/or are on the surface of theleather, providing a conductive network throughout the material. Insufficient amount, the capacitive material will create an electrostaticdischarge (ESD), comparable to that of the human body, enabling theleather to drive the software on capacitive or other types of touchscreen devices without the need for coupling to human skin/body.

Another embodiment of the present invention is directed to leatherproducts formed of such leather, such as garments, shoes, gloves,wallets, purses, furniture, shelters or other such applications wherethe end product would be real leather, with the unique performanceability to discharge static electricity or create an electromagneticinterference (EMI), for blocking certain bands of radio transmissionsand absorption of radio frequencies.

A further embodiment of the present invention is directed to a method ofimpregnating a material having an internal or external fiber matricesfor the purpose of providing additional performance capabilities notnormally found in such substrates as currently processed. The methodscomprise the steps of placing the material in a container, adding atanning agent to the container, adding a plurality of capacitiveparticles with a liquid to form a suspension, and adding the suspensionto the container and agitating the contents of the container until thecapacitive particles are embedded throughout the fiber matrices. Asufficient enough amount of the capacitive material is embedded so thatthe particles create a pathway for the electrons to discharge intoproviding the capacitive coupling without the need for human skincontact. In the method, the material can be either raw skins or tannedleather.

Yet a further embodiment of the present invention is directed to amethod of impregnating a material through the use of a finishing system.The finishing system could be any of, including combinations of a wateror solvent based leather finishing system, dye coat, or other suchsystems, which carry the conductive particles onto and/or into the fibermatrices, or coat the surface of the leather, in a high enoughconcentration, to create a conductive network along the surface and/orthrough the volume of the leather, to create a capacitive coupling,electrostatic discharge, or electromagnetic interference.

Leather Materials

The invention is also directed to leather products, including, but notlimited to, black leather products and colored leather products that areelectrically conductive. The term “colored leather” refers to white,red, magenta, cyan, black, yellow and any combinations thereof. Theleather products or materials of the invention may be created in thefollowing method. For lighter colors, such as white leather, it iscontemplated that a capacitive titanium dioxide material can be used,such as fluorine or zinc-doped titanium dioxide, such as that disclosedin U.S. Pat. No. 5,597,515 (Kauffman, et al., issued Jan. 28, 1997)which is herein incorporated by reference in its entirety.

A tanned leather (crust) is obtained. This leather may be tanned withconventional tanning agents, including chromium and or aluminum salts,vegetable based tannins, etc. The tanned leather is then colored bytumbling in a tumbling drum, using one or more of the following insolution: dyes, ionic additives, pH balancers, fastness agents, and/orwater.

Once the coloring process is complete, the leather is toggled. Togglinginvolves stretching the leather while wet to some percentage of themaximum stretch to which the leather can accept. For the leathermaterials of the current invention, the leathers are toggled to between25% and 75% of the maximum toggling, and preferably to 50% of themaximum toggling. While stretched (toggled), the leather material isthen dried, after which the dried leather is removed from the stretchingfixture.

The leather material is then optionally coated with a base coat. Saidbase coat comprises one or more of the following: (1) electricallyconductive filler material (for example carbon black particles such aslong chain carbon black particles, silver particles, silver coatedsilicates, silver coated copper particles, copper particles, nickel,tin, or aluminum particles or coated particles, conductive or coatedfibers or particles, etc.); (2) adhesion promoters; (3) bonding agents;(4) paints or other coloring agents; (5) aromatic polyurethane; (6)aliphatic polyurethane; (7) other carriers, including but not limited toresins, binders, cross linking agents, acrylics, etc.

This coating process is typically accomplished by spraying said coatingonto the leather surface, and said additives and binders cause said basecoat to bond to said leather material. Said long chain carbon blackforms long chain-like electrically conductive pathways within thecoating layer and the surface of the porous base leather material insuch a manner that said coated leather material maintains itsconductivity and capacitance when said leather material is bent,stretched, or otherwise deformed. The coating is then cured (dried)either under heat or air dried without heat. The resulting coating isboth electrically conductive (with an electrical conductivity belowabout 1.0×10⁶ Ohm-cm and chemically and/or mechanically bonded to theleather material.

A mid-coat optionally is then applied, comprising one or more of thefollowing: (1) aromatic polyurethane; (2) aliphatic polyurethane; (3)conductive fillers and/or (4) water.

This mid-coat is cured with or without heat. Said mid-coat is appliedwith electrically conductive fillers in such a concentration and in sucha manner that said conductive fillers form conductive pillar structuresthat bridge the thickness of said mid-coat, providing electricallyconductive continuity between the surface of said mid-coat and said basecoat.

A finish, or top, coat is then applied to the leather material tofurther condition the material by adding abrasion resistance, waterproofing, fire resistance, look and feel enhancement etc. A suitablewater-proofing agent to be used includes TFL-DRYWALK® (1% by dryweight). A suitable fire resistance agent to be used includes brominesalts, such as FLAMEPROOF fire retardants (FLAMEPROOF 1694, Apexical,Inc. Spartenburg, S.C.). It is contemplated that the modified materialcan be formulated with such fire retardants such that the material canwithstand temperatures of up to about 1400 degrees Fahrenheit or about1500 degrees Fahrenheit or greater. Such reagents can be added to theleather or fabric during the tanning, coloring and/or finishing process.The finish coating may be comprised of one or more of the followingconstituents: polyurethanes; acrylics; binders; look and feel enhancers;waxes; silicones; electrically conductive fillers; UV protectiveadditives; penetrating polymers, and/or water.

This coating may be applied very lightly to ensure electricalconductivity with and/or electrical capacitive coupling to the basecoating. Alternately, the finish coating may be loaded with conductivefillers in such a manner that said electrically conductive fillers formelectrically conductive pillars, or electrically conductive pathways,between the outer surface of said finish coat and said electricallyconductive mid- and base coatings.

The leather material then undergoes a final curing step in which thefinish coating is cured, typically with heat, but alternately withoutheat. After the final coating the leather is milled, by tumbling theleather material in a tumbler to restore flexibility, softness, and/orsuppleness.

Although the above method is specifically used for leather materials,the coatings and coating processes may be used on other materials suchas artificial leathers, and woven or non-woven fabric textiles such ascotton, polyester fiber, nylon fiber, vinyl fiber, silk, wool, lyocell,or other natural or artificial fibers.

The above described method of the invention produces a leather or othermaterial that is highly conductive, with a volume resistivity belowabout 1.0×10⁶ Ohm-cm, and/or has a capacitance approximately equivalentto that of the human body. This capacitance may be as low as 10pico-Farads (pF), or higher, such as about 50 pF, or about 100 pF, orabout 200 pF, or about 300 pF, or about 400 pF, or about 500 pF withrespect to a distant ground. In some embodiments, the capacitance isbetween about 10 pF and about 50 pF, or between about 10 pF and about500 pF, or between about 50 pF and about 500 pF.

The electrically conductive and capacitive materials of the inventionmay be then used in conventional or non-conventional methods to producegarments and various products, such as gloves, jackets, shirts, pants,coats, body suits, wet suits, boots, socks, hats, other clothing items,backpacks, belts, straps, bags, parachutes, upholstery, bedding,curtains, carpeting, computer bags, travel bags, duffel bags, etc.

The finished conductive and/or capacitive leather material of theinvention exhibits several functional, morphological, and structuralcharacteristics. The first of said functional characteristics is saidleather material's low electrical resistivity, as measured between twopoints on the coated surface of said leather material. The electricalresistivity of said coated leather material may be expressed as asurface resistivity or as a volume resistivity. The surface resistivityof the leather material of the invention is less than 1.0×10⁶Ohm/square, and the volume resistivity is less than 1.0×10⁶ Ohm-cm.

The next of said functional characteristics is said leather material'shigh capacitance with respect to a distant ground. The capacitance ofsaid electrically capacitive leather material is greater than 10.0 pF.

The next of said functional characteristics is said leather material'sability to maintain said low electrical resistivity and high capacitancewhen said leather material is stretched, twisted, bent, wrinkled,abraded, etc., without significant degradation to said electricalproperties.

Without being limited to any one theory, it is contemplated that theabove-mentioned functional characteristics are a result of one or moreof the following morphological and structural characteristics. The firstof said morphological and structural characteristics is penetration ofthe base coat into the porous and/or fibrous surface of said leathermaterial. During the coating process, one or more solvents, carriers,surfactants, polymers, or other liquids carries the electricallyconductive particles and/or fibers into the porous surface of saidleather material. During the ensuing curing process, one or more of saidsolvents, carriers, surfactants, polymers or other liquids evaporatesand or cross links, and/or cures, leaving the interstitial porousstructure of said leather material substantially filled with saidelectrically conductive particle and/or fiber material. Additionally,one or more polymers, waxes, fillers, binders, adhesives, or othermaterials may remain with said electrically conductive material in saidporous or fibrous structure of said leather material after curing. Thisinterstitially penetrated material combination forms a matrix of saidelectrically conductive materials, said binders, adhesives, polymers,waxes, etc. that is electrically conductive, possesses a capacitancewith respect to a distant ground, and not easily removed from thesurface of said leather material.

It is contemplated that the base and/or the mid coats provide thismatrix which penetrates the leather grain or flesh such that theelectrically conductive materials are sufficiently dispersed throughoutthe thickness of the leather. This dispersion allows the leather toretain its capacitive function in the event that the leather is worndown or damaged in some way.

The next of said morphological and structural characteristics is theexistence of a dense layer of electrically conductive material, such ascarbon black, on the surface of the coated base layer of said leathermaterial. The electrically conductive material in said base layer may beof sufficient concentration, buoyancy, surface tension, or otherproperty to allow said electrically conductive material to form asurface layer during the spray coating and/or curing process. Saidsurface layer acts as a highly electrically conductive layer on saidleather material, enabling both low electrical resistivity and highelectrical capacitance.

The next of said morphological and structural characteristics is theexistence of pillar like structures of conductive particles and/orfibers within one or more of the coating layers of said electricallyconductive and capacitive leather material. During the coating and/orcuring process, said electrically conductive particles and/or fibers insaid coating form closely packed structures within said coating layersuch that electrical pathways are formed which span the thickness ofsaid coating, creating matrix of electrically conductive pathways fromthe surface of said coating to the base of said coating. In this mannersaid coating may contain a dielectric binder, such as polyurethane, anda conductive filler, such as carbon black, and maintain a very lowelectrical resistivity once said coating and curing processes arecomplete.

The next of said morphological and structural characteristics is theexistence of electrically conductive fibers and/or electricallyconductive particles, within one or more of the coating layers of saidfinished leather material. Said long fibers (for example long chaincarbon black, or silver coated polymer fibers) form a structure withinsaid coating layer or layers in which said fibers and or particlesoverlap one another in such a manner that said coating may undergotensile, compressive, or shear strains (deformations) without sufferingsignificant loss of electrical conductivity. As the leather material andthe coating layer are deformed, said fibers and/or particles mayexperience small amounts of relative displacement yet maintainsufficient electrical conductivity so that said overall leather materialcontinues to maintain the desired electrical conductivity andcapacitance.

In one exemplary embodiment of the invention, described here, a blackcolored leather material is produced with a volume resistivity ofbetween 1.0×10³ and 1.0×10⁴ Ohm-cm, and a capacitance relative to adistant ground of between 50 pF and 500 pF. A tanned cattle leather istaken, having been tanned in a conventional leather tanning processusing chromium salts. Said tanned leather is then colored in tumblingdrum using a solution of carbon black leather pigment, water, ionicadditives, and pH balancers. Other chrome tanning processes or evenother basic mineral or vegetable tanning processes can be utilized asthe preliminary tanning method. Chromium sulfate, zirconium, aluminumand vegetable tannages may also be utilized with the present invention.

Said leather is then removed from the tumbling drum and toggled to 50%of its maximum stretch, or toggle. Said toggled leather is dried whilein this toggled state using a heater to accelerate the drying process.

Said toggled and dried leather is then removed from the toggling fixtureand a base coat is applied, said base coat comprising:

160 parts  aliphatic polyurethane and optionally a binder 160 parts water 60 parts Butyl Cellosolve Acetate 72 parts long chain conductivecarbon black particles 84 parts carbon black based leather pigment

Said base coat is sprayed onto the surface of said leather in such amanner as to uniformly and thoroughly coat said leather material. Saidcoated leather material is then cured, using heat to accelerate thecuring process.

A mid-coat is then applied to said coated leather, said mid-coatcomprising:

1 part Aliphatic Polyurethane optionally with binder 1 part AromaticPolyurethane optionally with binder 1 part water.

Said mid-coat is applied to said coated leather in a spray coatingprocess to evenly and thoroughly coat said leather material. Saidleather with said mid-coat is cured with heat to accelerate the curingprocess.

A finish coat is then applied to said coated and cured leather material,said finish coat comprising:

200 parts Cellulose Acetate Butyrate 100 parts water  18 parts Waxy feelenhancer

Said finish coat is applied to said coated leather material in a spraycoating process to evenly and thoroughly coat said leather material.Said leather with said finish coat is cured with heat to accelerate thecuring process.

Finally, said coated leather is milled by tumbling said coated and curedleather in a tumbler to restore flexibility and suppleness to saidleather material.

In a second exemplary embodiment of the invention, described here, a redcolored leather material is produced with a volume resistivity ofbetween 1.0×10¹ and 1.0×10⁵ Ohm-cm, and a capacitance relative to adistant ground of between 50 pF and 500 pF. A tanned cattle leather istaken, having been tanned in a conventional leather tanning processusing chromium salts. Said tanned leather is then colored in tumblingdrum using a solution of carbon black leather pigment, water, ionicadditives, and pH balancers.

Said leather is then removed from the tumbling drum and toggled to 50%of its maximum stretch, or toggle. Said toggled leather is dried whilein this toggled state using a heater to accelerate the drying process.

Said toggled and dried leather is then removed from the toggling fixtureand a base coat is applied, said base coat comprising:

66.6 parts Aliphatic polyurethane optionally with a binder  160 partswater  60 parts Butyl Cellosolve Acetate 3.33 parts Ashbury 5303 longchain conductive carbon black  30 parts Silver coated glass beads.

Said base coat is sprayed onto the surface of said leather in such amanner as to uniformly and thoroughly coat said leather material. Saidcoated leather material is then cured, using heat to accelerate thecuring process.

A color coat is then applied to said coated and cured leather material,said color coat comprising:

10 parts Aliphatic Polyurethane and optionally a binder  5 parts Redcolor pigment 10 parts Silver coated glass beads 1 part Long chainconductive carbon black 10 parts water.

Said color coat is applied to said coated leather in a spray coatingprocess to evenly and thoroughly coat said leather material. Saidleather with said color coat is cured with heat to accelerate the curingprocess.

A mid-coat is then applied to said coated leather, said mid-coatcomprising:

10 parts Aliphatic Polyurethane optionally with binders; 10 partsAromatic Polyurethane optionally with binders; 10 parts Silver coatedglass beads; 1 part Long chain conductive carbon black; and 10 partswater.

Said mid-coat is applied to said coated leather in a spray coatingprocess to evenly and thoroughly coat said leather material. Saidleather with said mid-coat is cured with heat to accelerate the curingprocess.

A finish coat is then applied to said coated and cured leather material,said finish coat comprising:

200 parts Cellulose Acetate Butyrate 100 parts Silver coated glass beads 10 parts Long chain conductive carbon black 100 parts water  18 partsWaxy feel enhancer  10 parts UV protective additive

Said finish coat is applied to said coated leather material in a spraycoating process to evenly and thoroughly coat said leather material.Said leather with said finish coat is cured with heat to accelerate thecuring process.

Finally, said coated leather is optionally milled by tumbling saidcoated and cured leather in a tumbler to restore flexibility andsuppleness to said leather material. Such material is referred to hereinas “finished”, or being in “finished form”.

Other Materials

It is further contemplated that similar procedures could be used onvinyl resins using standard vinyl manufacturing processes whichtypically employ vinyl and plasticizers. The vinyl and plasticizers arestirred together in a vat and then mixed with AZO compound (havingcarbon and nitrogen) and heated to make a foam with the consistency ofpancake batter. Silver, copper, nickel and/or carbon black power maythen be added to the base polymer along with other pigments. This slurrymay then be poured onto an appropriate backing sheet, such as felt,fleece (microfleece), suede or a velvet-like napped surface to providestrength and flexibility. This may then be put through a reverse rollcoater machine, heated in an oven until the vinyl resin absorbed theplasticizers and started to set. Then the sheets may be run through aprinting press with plates that were designed to imprint the texture orgrain of leather into the vinyl material. If further coloring weredesired, additional sprays of colorants may be added in a manner thatdoes not affect the conductivity. In some embodiments, the modifiedmaterial is produced using yarn wherein at least a portion of the yam iscapacitive yarn. In some embodiments, the modified material whichcomprises capacitive yam is not further treated or coated withconductive material. In another embodiment, the modified material whichcomprises capacitive yam is woven such that the material has a uniformconductivity throughout the material.

Woven or knitted materials can be impregnated with a conductivematerial, such as metal oxides, metal fibers or a carbon-black basedmaterial. The impregnation step is such that the conductive material isused to fabricate a bolt of capacitive fabric. For example, theconductive fibers are blended with an organic or inorganic material,such as cotton, nylon, polyester and the like, to form a capacitiveyarn. The capacitive yam is then woven or knit with a non-capacitiveyarn which can be either an organic or inorganic material, such ascotton, nylon, polyester and the like, to form a capacitive fabric.

Suitable conductive materials to be used in the capacitive yam areThunderon (Static Faction, Inc.) which is an organic fiber of coppersulfide chemically bonded to acrylic and nylon fibers, SHIELDEXmetalized yarns and conductive sewing threads which are silver-based,and Resistat® (Jarden Applied Materials) which is a nylon fiber withelectrically conductive carbon particles which become part of thestructure of the fiber. Ideally, with the conductive yarn would retainthe strength and flexibility of the organic or inorganic yam materialwhile maintaining excellent conductivity.

In the woven or knitted capacitive fabric, the capacitive yarn shouldaccount for at least about 0.6 to about 23% of the yam in the fabric andshould result in a surface resistivity of at least about 3×10⁵ Ohm/cm.This amount depends on the type of conductive material used. Forexample, when a highly conducive material, such as the silver-basedyarn, is used the amount of conductive yarn required would be less.However, when a carbon-based yarn is used, a higher percentage may berequired to achieve the desired resistivity. For example, a capacitivematerial can be made by weaving or knitting a bolt of fabric using 85%non-capacitive thread (e.g. polyester) with 15% capacitive thread (e.g.Resistat®). The capacitive thread would thus be uniformly distributedthroughout the conductive woven or knitted fabric. Therefore, a garmentsuch as a glove made from the above-described conductive fabric would becapacitive throughout the garment. Additionally, the conductive fabricas disclosed herein can be laundered multiple times (i.e. more than 10times, or more than 50 times, or more than 100 times) in a standardwash/dry cycle without any observable depletion in the conductiveproperties.

The conductive fabric is designed to interact with touch screen devicesand can be used to make a garment such as a glove for use with a touchscreen device. However, the conductive coupling of the touch screen isto the conductive material, not to a hand or body part in contact withthe conductive material. In some embodiments, the glove will stilloperate the touch screen device without a human hand inside the glove.Therefore, a glove made from the conductive fabric as disclosed hereincan be used by an amputee.

In one embodiment, the modified material has a volume resistivity ofless than about 3.0×10⁵ Ohm-cm, or alternatively, less than about3.0×10⁶ Ohm-cm, or alternatively, less than about 1.0×10⁶ Ohm-cm and/ora surface resistivity of less than about 3.0×10⁵ Ohm-cm, oralternatively, less than about 3.0×10⁶ Ohm-cm, or alternatively, lessthan about 1.0×10⁶ Ohm-cm.

Glove Embodiments

The modified materials of the invention may be used in a number ofcapacities as described above allowing a user to operate a capacitivetouch screen. Briefly stated, provided is a modified material whichcomprises electrically conductive material and/or chemical treatments,to enable a capacitive coupling to Capacitive and Projected CapacitanceTouch Screen devices and any other types of touch screen devices,regardless of the touch screen technology used. The modified materialprovides for either a projected capacitance of the human body throughthe material to the interface, or a direct capacitive coupling to thetextile itself, thereby not requiring human contact to operate the touchscreens or touch pads. The modified material can be fabricated into afunctional article of clothing, such as a glove or other item made of awoven or knitted textile so as to increase the functionality of thearticle of clothing or item made thereof. The conductive material cancreate a bridge to PCT devices, wherein the conductive materialcomprises integrated components, or chemical treatments serving as aconnection to the devices without the need for the human body to createthis capacitive coupling. As shown in the drawings, the describedembodiments of the modified material of the invention are embodied in aconductive glove, wherein the conductive glove allows a user of theconductive glove to operate a touch screen device without removing theglove. The gloves of the invention also provide a barrier from certainviruses, bacteria and fungi that can easily be passed from interactingwith previously contaminated touch screen surfaces during interaction.

FIG. 1 shows a cross-section of an embodiment of an electricallyconductive glove. This embodiment includes a liner 110, a conductiveinsulator 120 and an outer shell 130. It is to be understood that thisis a cross-section of at least a portion of the glove. That is, theentire glove is not required to be fabricated as shown. In anapplication, the glove is worn by a user of a touch screen device. Anembodiment includes the portion of the glove that the user uses tocontrol the touch screen device being fabricated as shown by thecross-section view of FIG. 1.

For an embodiment, the liner and outer shell being less than 2 mm orless than 1 mm or less than 0.5 mm thick and/or has a volume resistivityof less than 1.0×10⁶ Ohm-cm and/or a surface resistivity of less than1.0×10⁶ Ohm-cm. When any material has an electrical volume resistivitylevel of less than 1.0×10⁶ Ohm-cm or a surface resistivity of less than1.0×10⁶ Ohm-cm it is widely considered to be in the range of aconductive material. This is desirable because a capacitive couplingwith the touch screen is not possible if the non-conductive liner and/orthe outer shell is thicker than 0.5 mm and not made of a conductivematerial.

In order to properly operate a capacitive touch screen device withgloves on, without the use of a device, such as a stylus or otherembodiment specifically created for this purpose, the glove itself mustprovide a capacitive coupling to the human skin. This can be achieved byemploying/using material as described throughout that will not block theconductivity to the human skin surface. When a fabric or material isused that is either too thick, or has a volume resistivity of greaterthan 1.0×10⁶ Ohm-cm and/or a surface resistivity of greater than 1.0×10⁶Ohm-cm, the results are a material that is electrically dissipative orinsulative, not conductive and therefore will not work for thisapplication.

Various embodiments of the liner include at least one of rayon, acetate,nylon, modacrylic, olefin, PLAY polyester, wool, cotton, silk, acrylic,blends or any type of conductive woven fiber blends, metallic fibers orfibers treated with copper, silver, carbon black, carbon fiber, nickel,tin or other conductive material with a thickness of less than 0.5 mmand/or a volume surface resistivity of less than 1.0×10⁶ Ohm-cm and/or asurface resistivity of less than 1.0×10⁶ Ohm-cm.

For an embodiment, the electrically conductive insulator layer islocated adjacent to the liner. Additionally, this embodiment includes aresistance of the electrically conductive insulator layer being lessthan 1.0×10⁶ Ohm-cm.

Embodiments of the electrically conductive thermal insulator layerinclude a conductive foam, fiber, microfiber, microfilament, plastic,metal, rubber or breathable thermal insulation with a volume resistivityof less than 1.0×10⁶ Ohm-cm and/or a surface resistivity of less than1.0×10⁶ Ohm-cm.

Configurations of the conductive fiber, microfiber, microfilament orbreathable thermal, electrically conductive, thermal insulation includematerials made from different mixtures of polymers, but primarilypolyethylene terephthalate or a mixture of polyethylene terephthalateand polypropylene. Other materials may include polyethyleneterephthalate, polyethylene isophthalate copolymer and acrylic incombination with a conductive coating or impregnated, embedded,compounded or plated conductive material with a surface resistivity ofless than 1.0×10⁶ Ohm-cm. This can be accomplished by the use of achemical reaction to bond the molecules of carbon black, copper, silver,gold, nickel, tin or other conductive metal substances, with themolecules of the host fiber, or by plating or compounding any of theseconductive substances to the host fiber.

Other embodiments of the electrically conductive insulator layer includea conductive foam, rubber, fiber, microfiber or microfilament.

For an embodiment, the outer shell is formed adjacent to theelectrically conductive insulating layer. Additionally, this embodimentincludes the outer shell being less than 2 mm thick and/or having avolume resistivity of less than 1.0×10⁶ Ohm-cm.

This is desirable because a capacitive coupling with the touch screen isnot possible if the non-conductive liner and/or the outer shell isthicker than 0.5 mm and not made of a conductive material.

In order to properly operate a capacitive touch screen device withgloves on, without the use of a device, such as a stylus or otherembodiment specifically created for this purpose, the glove itself mustprovide a capacitive coupling to the human skin. This can be achieved byemploying or using key types of fabrics or other materials that will notblock the conductivity to the human skin surface. When a fabric ormaterial is used that is either too thick, or has a volumetric and/orsurface resistivity of greater than 1.0×10⁶ Ohm-cm, the results are amaterial that is electrically dissipative or insulative, not conductiveand therefore will not work for this application.

Embodiments of the outer shell include rayon, acetate, nylon,modacrylic, olefin, PLA, polyester, wool, cotton, silk, acrylic, blendsor any type of conductive woven fiber blends; metallic fibers or fiberstreated with copper, silver, carbon black, carbon fiber, nickel, tin,other conductive material, animal skin, vinyl, rubber, latex orsilicone.

The embodiment of FIG. 1 can be fabricated by using a piece of fabricmade of wool, cotton or silk as a liner, for instance, and securing itto a layer of electrically conductive thermally insulative foam, orelectrically conductive thermally insulative microfiber insulation, forinstance, and securing the insulation to the outer shell. When allcomponents of the glove meet the specifications of both thickness andconductivity. By simply pressing the skin firmly against the threelayers of material will produced the desired results of creating acapacitive coupling through the dielectric and conductive surfaces tothe touch screen device and allows the user to use the device as if theywere touching the device with their bare skin.

FIG. 2 shows a cross-section of another embodiment of an electricallyconductive glove. This embodiment additionally includes at least oneconductive channel 210. Each of the conductive channels 210 extends froman inner surface of the outer shell 130 to an outer surface of the outershell 130

Embodiments of the conductive channels 210 include conductive materialwhich may include resins, polymers, plastics, rubbers, foams, fibers,metals, epoxies or adhesives. The conductive channels provide enhancedconductivity between the skin of the user's hand and the externalsurface of the glove as defined by the outer surface of the outer shell130.

One method of manufacturing the conductive channels includes perforatingthe outer shell material (before forming the glove with the conductivethermal insulator 120 and the liner 110) and filling the perforationswith a conductive gel, adhesive, resin, foam, plastic, metal or fibroussubstrate that meets the criteria of being conductive. The number ofperforations can number from one to as many as desired in differingdiameters, for the purpose of covering the surface area adequately toallow the user to interact with the device in the same manner they wouldif they were not wearing gloves. The perforations can be spaced inspecific patterns for either aesthetic design or for materials thatwould normally be weakened by holes in material to allow for thestrength of the material to not be compromised, provided that thefunction of allowing conductive interaction between the user and thedevice are not compromised.

FIG. 3 shows a cross-section of another embodiment of an electricallyconductive glove. This embodiment additionally includes an outerconductive layer 310 adjacent to the outer surface of the outer shell.

Embodiments of the outer conductive layer 310 include a base coating ofpolyurethane, polyepoxide, paint, adhesive, sealant, silicone, resins,polymers, plasticizers, vinyl compounds, metals or plastics materialswith an added electroconductive carbon, silver, nickel, copper, tin,gold or other conductive metal or alloy into the coating in highconcentrations to achieve a volume resistivity of less than 1.0×10⁶Ohm-cm which may or may not be specifically used to mimic the color,grain, texture and feel of the outer surface of the outer shell.

An optional additional layer includes a color layer 320 adjacent theouter conductive layer 310. Embodiments of the color layer are primarilyaesthetic, and can be used to determine a glove color, texture, grain orappearance.

A method of manufacturing the glove structure as shown in FIG. 3include, for example, an organic or inorganic fabric or material that isdesigned for the comfort and warmth of the user and functions as amethod of wicking away moisture while allowing conductance to takeplace. The materials may be made of cotton or wool, for instance andmeet the criteria of thickness and conductance needed. Adjacent to theliner would be the electrically conductive thermally insulativematerial; adjacent to the insulative material would be the outer shellwith the conductive channels. Adjacent to the outer shell would be anouter conductive layer, which may or may not be colored or textured tomatch the outer surface of the outer shell.

FIG. 4 shows a cross-section of another embodiment of an electricallyconductive glove. This embodiment includes an outer shell 130. As shown,the outer shell 130 includes at least one conductive channel 210. Eachof the conductive channels extend from an inner surface of the outershell 130 to an outer surface of the outer shell 130. For an embodiment,each of the conductive channels has a volume and/or surface resistivityof less than 1.0×10⁶ Ohm-cm.

Perforating the outer shell material (before forming the glove with theconductive thermal insulator 120 and the liner 110) and filling theperforations with a conductive gel, adhesive, resin, foam, plastic,metal or fibrous substrate that meets the criteria of being conductive.The number of perforations can number from one to as many as desired indiffering diameters, for the purpose of covering the surface areaadequately to allow the user to interact with the device in the samemanner they would if they were not wearing gloves. The perforations canbe spaced in specific patterns for either aesthetic design or formaterials that would normally be weakened by holes in material to allowfor the strength of the material to not be compromised, provided thatthe function of allowing conductive interaction between the user and thedevice are not compromised.

Alternate embodiments can additionally include one or more outerconductive layers 310 adjacent to the outer surface of the outer shell310. The addition of the conductive layer 310 provides the ability touse less perforations, as few as one, that can be strategically placedin inconspicuous areas of the glove and provide a capacitive couplinganywhere on the treated surface of the outer surface of the outer shell.

A method of manufacture for the outer conductive layer includes, forexample thin coat of conductive coating bonded to the outer surface ofthe outer shell by means of spraying, painting, heat/pressure bonding orby the use of a conductive adhesive material.

Once the material is made to be conductive, the material is said to bein “finished form”.

Another embodiment includes a color layer 320. Embodiments of the colorlayer 320 color layer are primarily aesthetic, and can be used todetermine a glove color, texture, grain or appearance.

The color layer can be formed by use of a chemical bonding, mechanicalbonding or by spraying, painting, heat/pressure bonding or by the use ofa conductive adhesive or primer coating.

Additional Glove Embodiments

Additional embodiments of the glove are discussed below. In oneembodiment, the invention is directed to a conductive glove comprising:

a liner, the liner being less than 2 mm thick and/or having a resistanceof less than 1.0×10⁶ Ohm-cm;

an electrically conductive insulator layer, with a resistance of lessthan 1.0×10⁶ Ohm-cm, adjacent to the liner; and

an outer shell adjacent to the electrically conductive insulating layer,the outer shell being less than 2 mm thick and/or having a resistance ofless than 1.0×10⁶ Ohm-cm.

In one embodiment, the glove when worn by a user, at least a portion ofthe liner physically contacts the user's hand. The liner optionally maycomprise at least one component selected from of rayon, acetate, nylon,modacrylic, olefin, PLAY polyester, wool, cotton, silk, acrylic, blendsor conductive woven fiber blends, metallic fibers or fibers treated withcopper, silver, carbon black, carbon fiber, nickel, tin or otherconductive material with a thickness of less than about 2 mm. In oneembodiment, the material has a volume resistivity of less than about3.0×10⁵ Ohm-cm, or alternatively, less than about 3.0×10⁶ Ohm-cm, oralternatively, less than about 1.0×10⁶ Ohm-cm and/or a surfaceresistivity of less than about 3.0×10⁵ Ohm-cm, or alternatively, lessthan about 3.0×10⁶ Ohm-cm, or alternatively, less than about 1.0×10⁶Ohm-cm.

The electrically conductive thermal insulator layer comprises aconductive foam, fiber, microfiber, microfilament, plastic, metal,rubber or breathable thermal insulation with a volume resistivity ofless than 1.0×10⁶ Ohm-cm and/or a surface resistivity of less than1.0×10⁶ Ohm-cm.

The conductive fiber, microfiber, microfilament or breathable thermal,electrically conductive, thermal insulation comprises materials madefrom different mixtures of polymers, but primarily polyethyleneterephthalate or a mixture of polyethylene terephthalate andpolypropylene. Other materials may include polyethylene terephthalate,polyethylene isophthalate copolymer and acrylic in combination with aconductive coating or impregnated, embedded, compounded or platedconductive material with a surface resistance of less than 1.0×10⁶Ohm-cm. This can be accomplished by the use of a chemical reaction tobond the molecules of carbon black, copper, silver, gold, nickel, tin orother conductive metal substances, with the molecules of the host fiber,or by plating or compounding any of these conductive substances to thehost fiber.

The electrically conductive thermal insulator layer comprises aconductive foam, rubber, fiber, microfiber or microfilament.

The outer shell may comprise at least one conductive channel, theconductive channel extending from an inner surface of the outer shell toan outer surface of the outer shell. The glove may further comprise anouter conductive layer adjacent to the outer surface of the outer shell.The outer conductive layer comprises a base coating of polyurethane,polyepoxide, paint, adhesive, sealant, silicone, resins, polymers,plasticizers, vinyl compounds or plastics materials with an addedelectro-conductive carbon, silver, nickel, copper, tin, gold or otherconductive metal or alloy into the coating in high concentrations toachieve a surface and/or volumetric resistivity of less than 1.0×10⁶Ohm-cm which may or may not be specifically used to mimic the color,grain, texture and feel of the outer surface of the outer shell.

The glove may also have a color layer adjacent the outer conductivelayer, the color layer determining a glove color, texture, grain orappearance.

In another embodiment, the invention is directed to a conductive glovecomprising: an outer shell, the outer shell comprising at least oneconductive channel, the conductive channel extending from an innersurface of the outer shell to an outer surface of the outer shell, theconductive channel having a resistivity of less than 1.0×10⁶ Ohm-cm. Theglove may also have one or more outer conductive layers adjacent to theouter surface of the outer shell.

In another embodiment is provided a conducting glove comprising anonconductive dielectric outer shell, the non-conductive outer shellbeing less than 0.5 mm thick and electrically conductive thermalinsulator layer, with a volume resistivity of less than 1.0×10⁶ Ohm-cm,adjacent to the liner; and an inner liner adjacent to the electricallyconductive insulating layer, the inner liner being less than 2.0 mmthick or with a volume resistivity of less than 1.0×10⁶ Ohm-cm where thecapacitive touch screen is capacitively coupled to the conductivethermal insulator layer, which in turn is electrically conductive to theconductive inner liner, which in turn is electrically conductive to theuser's skin. The conducting and insulating layers are located only atspecific locations on the glove, such as the finger and thumb tips.

In another embodiment, is provided a conducting glove comprising anonconductive dielectric outer shell, the non-conductive outer shellbeing less than 0.5 mm thick an electrically conductive thermalinsulator layer, with a volume resistivity of less than 1.0×10⁶ Ohm-cm,adjacent to the liner; and a non-conductive dielectric inner lineradjacent to the electrically conductive insulating layer, the innerlayer being less than 0.5 mm thick where the capacitive touch screen iscapacitively coupled to the conductive thermal insulator layer, which inturn is capacitively coupled to the user's skin. The conducting andinsulating layers are located only at specific locations on the glove,such as the finger and thumb tips.

In still another embodiment is provided a conducting glove comprising anelectrically conductive outer shell, the electrically conductive outershell with a volume resistivity of less than 1.0×10⁶ Ohm-cm anelectrically conductive thermal insulator layer, with a volumeresistivity of less than 1.0×10⁶ Ohm-cm, adjacent to the liner; and anon-conductive dielectric inner liner adjacent to the electricallyconductive insulating layer, the inner liner being less than 0.5 mmwhere the capacitive touch screen is electrically conductive to theouter shell, which in turn is electrically conductive to the thermalinsulator layer, which is capacitively coupled to the user's skin. Theconducting and insulating layers are located only at specific locationson the glove, such as the finger and thumb tips. The conductive fiber,microfiber, microfilament or breathable thermal, electricallyconductive, thermal insulation comprise materials made from differentmixtures of polymers, but primarily polyethylene terephthalate or amixture of Polyethylene terephthalate and polypropylene. Other materialsmay include polyethylene terephthalate, polyethylene isophthalatecopolymer and acrylic in combination with a conductive coating orimpregnated, embedded, compounded or plated conductive material with asurface resistance of less than 1.0×10⁶ Ohm-cm. This can be accomplishedby the use of a chemical reaction to bond the molecules of carbon black,copper, silver, gold, nickel, tin or other conductive metal substances,with the molecules of the host fiber, or by plating or compounding anyof these conductive substances to the host fiber.

The electrically conductive insulator layer may comprise a conductivefoam, rubber, fiber, microfiber or microfilament.

The outer shell may comprise at least one conductive channel, theconductive channel extending from an inner surface of the outer shell toan outer surface of the outer shell. The glove may further comprise anouter conductive layer adjacent to the outer surface of the outer shell.

The outer conductive layer comprises a base coating of polyurethane,polyepoxide, paint, adhesive, sealant, silicone, resins, polymers,plasticizers, vinyl compounds or plastics materials with an addedelectro-conductive carbon, silver, nickel, copper, tin, gold or otherconductive metal or alloy into the coating in high concentrations toachieve a surface and/or volumetric resistance of less than 1.0×10⁶Ohm-cm which may or may not be specifically used to mimic the color,grain, texture and feel of the outer surface of the out shell.

The glove may further comprise a color layer adjacent the outerconductive layer, the color layer determining a glove color, texture,grain or appearance.

In still yet another embodiment, the invention is directed to aconductive glove comprising: an outer shell, the outer shell comprisingat least one conductive channel, the conductive channel extending froman inner surface of the outer shell to an outer surface of the outershell, the conductive channel having a resistance of less than 1.0×10⁶ohm-cm. The glove may further comprise one or more outer conductivelayers adjacent to the outer surface of the outer shell.

Also encompassed by the invention is a glove with a non-conductivelayer, but that allows capacitive coupling between the screen and aconductive insulation material, or between the conductive insulationmaterial and the finger.

In yet another embodiment, the invention is directed to a conductive orcapacitively coupled glove that is only locally conductive orcapacitively coupled, for example in the finger tip but not elsewhere. Aglove that is a single conductive layer, for example, is just an outershell.

In the following embodiment and method an electrically conductive glovesuitable for interaction with a capacitive touch screen is described. Anelectrically conductive glove of the invention is fabricated in such amanner that the glove material, which may be non-conductive, ordielectric, initially, is coated, or treated, with a thin film of aconductive material. The material of the glove, for example leather,faux leather, suede, polymer, wool, cotton, fur, nylon, fleece, or anyother suitable material, is coated in such a way that an electricallyconductive surface layer is created on the outside of the glove. Thiselectrically conductive coating may or may not penetrate into thematerial of the glove, but must a form an electrically conductivesurface or surface layer when coated. In this manner the electricallyconductive coating creates an electrical capacitance relative to adistant ground, or to the capacitive touch device, sufficient to bedetected by a capacitive touch device with or without any grounding to auser or other ground source. To affect such an electrical capacitance,the surface area, geometry of the coating, electrical conductivity,and/or the volume of conductive material are sufficient to create anelectrical capacitance relative to a distant ground, or to thecapacitive touch device, sufficient to be detected by the capacitivesensors in the capacitive touch device. The conductive coating may beelectrically conductively connected to the user, it may be electricallycapacitively coupled to the user, or it may be electrically isolated.

A method for manufacturing of the electrically conductive glovedescribed above is described here. A glove material is coated with anelectrically conductive coating in such a manner as to coat the surface,penetrate the glove material, fill pores in a porous material, fillpores in a fibrous material, coat the fibers of a fibrous material, orotherwise render the material electrically conductive on or near itssurface. The electrically conductive coating material may be generallymanufactured by using a carrier, for example a plasticizer, a bulkpolymer like acrylic, a weather proofing, a leather conditioner, anenamel, or any other suitable carrier, and filling said carrier with anelectrically conductive medium, such as powdered carbon in the form ofgraphite or carbon black, powdered metal like silver, powderedindium-tin-oxide (ITO), electrically conductive polymers, or otherpowdered electrically conductive material or materials. The electricallyconductive material may also be manufactured as a solution of one ormore conductive materials, in one or more carriers and/or solvents. Saidelectrically conductive coating material is then applied to said glovematerial in such a fashion as to coat the surface, bond to the surface,and/or penetrate the surface in such a fashion as to create anelectrically conductive surface, or near surface, layer on said glovematerial. Such electrical volume conductivities of said electricallyconductive glove materials should preferably be less than 1.0×10⁶Ohm-cm, more preferably less than 1.0×10⁵ Ohm-cm, and most preferablyless than 1.0×10⁴ Ohm-cm.

A glove pattern is then cut from said electrically conductive materialand fabricated in any standard or non-standard glove fabrication processsuch that the electrically conductive surface is positioned preferablyon the outside of one or more of the materials of the finished glove,but may be positioned on the inside of one or more of the materials ofthe finished glove.

The carbon black impregnated leather can be made into gloves or othertypes of instruments where a capacitive coupling is needed. Due to thetreatment of this particular leather as disclosed herein, there is noneed for capacitive coupling from the screen through the leather to thehuman body, as the leather itself is capable of capacitively coupling tothe device. The leather is suitable for all products, such as gloves,where the need for capacitive coupling without human contact to thescreen is required. Accordingly, a leather is provided herein whichcarbon black, or other electrically conductive agent, is suspended andtrapped within the fiber matrix of the skins to create an internalcapacitive network.

In one embodiment, the present invention is directed to a glovecomprising a tanned leather or leather-like material having an internalfiber matrix; an electrically conductive agent bonded to the tannedleather or leather-like material so that the electrically conductivematerial penetrates the internal fiber matrix of the leather orleather-like material and are trapped and bonded to the fiber matrix;and the electrically conductive agent creates a capacitive networkthroughout the substrate and enables a capacitive coupling to amulti-touch capacitive touch screen without the need of an electronbridge to the human body.

In another embodiment, the present invention is directed to apparelwhich comprises a textile as disclosed herein having a fiber matrixwhich is capable of capacitively coupling to a multi-touch capacitivetouch screen without the need of an electron bridge to the human body.

Yet another embodiment of the present invention is directed to a garmentwhich comprises tanned leather or leather-like material as disclosedherein having an internal fiber matrix; an electrically conductive agentbonded to the leather or suffused to the fibers so that the electricallyconductive agent penetrates the internal fiber matrix and are trappedwithin and bonded to the internal fiber matrix; and the trappedparticles in the leather allow an electrostatic discharge of 1×10⁵ orless.

Yet another embodiment of the present invention is directed to footwearwhich comprises the tanned leather or leather-like material as disclosedherein having an internal fiber matrix; an electrically conductive agentbonded to the leather or suffused to the fibers so that the electricallyconductive agent penetrates the internal fiber matrix and is trappedwithin and/or bonded to the internal fiber matrix; and the electricallyconductive agent in the leather or leather-like material provide for anelectrostatic discharge of 1×10⁵ or less.

EXAMPLES

The following formulations can be used in the compositions and methodsdisclosed herein.

Tanning Example 1 Tanning and Leather Preparation

Leather tanning is an ancient art, having its beginnings in South Asiasomewhere between 7000-3300 BC. Leather tanning has been practiced on awide variety of materials. The process described herein can be appliedto many raw materials, for example including but not limited to sheep,goat, cow, deer, horse, reptile, bird, pig and kangaroo skin. The rawmaterial depends upon the application for the final leather productrequired.

All animal skins are made of a fiber matrix that consists of water,protein, fatty material and mineral salts. These include elastin,collagen, keratin, albumens, globulins, mucins and mucoids. The proteinmay consist of many types, but the important ones are collagen which, ontanning, gives leather.

In the first embodiment of the method of the present invention, the rawmaterial is brought to a fully chrome-tanned state, which impartspermanency to fiber structure. The chrome tanning process is describedin Leather Technicians Handbook by J.H. Sharphouse, B.S.c. LeatherProducers Association, Kings Park Road, Moulton Park, Northampton, NN31JD U.K. includes a series of steps as is discussed below.

1. First the skins are soaked in drums running at four revolutions perminute with 300% water at 27° Celsius and adjusted to a pH of 9.0 with0.1% non-ionic surfactant. The skins are drummed intermittently for aperiod of 6 to 12 hours.

2. The skins are then drained.

3. The flesh sides of the skins are painted with 15% sodium hydrogensulfide (33% strength), 50% hydrated lime and 35% water. The skins areallowed to pile overnight and then the wool is removed.

4. Next, 600% water and 12% lime are placed in a vat with agitatingpaddles run five minutes every four hours for 24 hours. Then 12% sodiumsulfide is added to the vat and the agitating is continued for anadditional 12 hours.

5. Next, the flesh is removed from the back side of the skin with arotary fleshing machine.

6. Next, the skin is washed in soft, running water in a paddle vat for30 minutes.

7. The skins are de-limed in paddle vats containing 500% water at 37°Celsius with 1.5% ammonium chloride where the paddles are run for 60minutes or until the skins are free of lime.

8. The bating process includes the addition of 1% bacterial bate withthe paddles run for two to three hours.

9. Next the skins are pickled in a drum with the pickling liquor beingformed of 200% water at 20° Celsius, 20% salt and 2% sulfuric acid. Thedrum is run for 60 minutes, with the final pickle liquor strength beinga 0.5% solution of sulfuric acid. The drum is then drained and the skinsare stored for aging for several days.

10. The Chrome tanning solution is put in the drum. The tanning solutionincludes 100% water, 5% salt, 1% chromic oxide (as 10% of chrome liquorof 11% chromic oxide and 33% basicity, SO₂ reduced) and then 1% chromicoxide (as 10% of the chrome liquor). The skins are then drummed for fromtwo to six hours in this mixture until penetrated.

11. The skins are then basified. To complete the tannage between about3% to about 15%. 0.5-1% sodium bicarbonate should be added carefullyover four hours and then a shrinkage temperature test should be taken.At the completion of tannage, the pH should be approximately 4.4 and theshrinkage temperature 98° Celsius.

12. The skins are then piled and drained for 24 hours.

13. Then the skins are neutralized thoroughly in the drum with 150%water and 1.5% ammonium bicarbonate.

14. Finally, the skins are washed well, at which point the leather isfully chrome tanned and ready for the re-tanning by the impregnationprocess of the present invention.

The chrome tanning process described above is well known in the art. Itis provided as a guideline of the primary tanning process performed onthe raw skins prior to the re-tanning process for impregnation ofcapacitive material of the present invention.

Other chrome tanning processes or even other basic mineral or vegetabletanning processes can be utilized as the preliminary tanning method.Chromium sulfate, zirconium, aluminum and vegetable tannages may also beutilized with the present invention.

Formulation Example 1 Leather

The leather (Full Grain Hair Sheep Skin) is sprayed with two layers ofthe base coat, first at a thickness of from 6.5 to 7.0 G/FT² (wet), thenat a thickness of 6.0 G/FT² (wet), and then is plated (Sand, 90 ° C., 50Kg). A top coat is sprayed to a thickness of from 1.5 to 2.0 G/FT² (wet)and the leather is subjected to a roto press at 250 ° C. (low pressure).Finally, the leather can be milled to achieve the desired visual andtextile effect.

Base Coat: Material Used Parts Water 35 Glycol Ether EP 20 UnithaneIC-1600 25 Unithane IC-1500 15 Pigment 2.5 Black Carbon Powder 2.5 Note:The base coat is not filtered before use.

Top Coat: Material Used Parts Water 46.4 Unithane IC-1400 25 UnithaneIC-1800 25 Additive IC-04 0.8 Additive IC-05 0.8 Hardener CN 2

Formulation Example 2 British Tan Leather

The leather (Full Grain Goat Skin) is sprayed with one layer of the basecoat (wet), two layers of the mid coat, and one layer of the top coat(medium coat). The leather is then tumbled.

Base Coat: Material Used Parts Water 30 Glycol Ether EP 15 UnithaneIC-1600 30 Unithane IC-1500 10 Pigment 13 Black Carbon Powder 2

Mid Coat: Material Used Parts Water 25 Glycol Ether EP 10 UnithaneIC-1600 45 Unithane IC-1500 5 Pigment 15 Black Carbon Powder 0.5

Top Coat: Material Used Parts Water 46.4 Unithane IC-1400 25 UnithaneIC-1800 25 Additive IC-04 0.8 Additive IC-05 0.8 Hardener CN 2

Formulation Example 3 Finished Felt

The felt is first dipped in base coat and allowed to dry in an oven at85 ° C. The top coat is then sprayed on the treated felt.

Base Coat: Material Used Parts Water 35 Glycol Ether EP 20 UnithaneIC-501 25 Unithane IC-1500 15 Pigment 2.5 Black Carbon Powder 2.5

Top Coat: Material Used Parts Water 46.4 Unithane IC-1400 25 UnithaneIC-1800 25 Additive IC-04 0.8 Additive IC-05 0.8 Hardener CN 2

Method Example 1 Impregnating the Leather

1. The leather is washed at 110° Fahrenheit for approximately 1 hourwith 200% water of Dry Weight of leather and 1% Formic acid, 1%detergent, 1% wetting agent and 1% Chelating agent added to the bath.

2. The leather is then rinsed at 110° for 10 minutes.

3. The leather is then re-floated at 90° F. 100% of dry weight for 30minutes. 1% Formic acid, 10% gluteraldehyde, 25% carbon black is addedto the bath.

4. A fat liquor at 6% of dry weight is then added to the bath whichconsists of a paraffin wax and this is run for three hours.

5. After 3 hours, 20% of the self pacifying chrome is added to the bathand this is run for 3 hours.

6. At the end of the runtime, the leather is then washed and 90° F. for10 minutes and then cooled at 70° F. for 10 minutes.

7. At this point the carbon black has fully penetrated the fiber matrixof the skins and has bonded with the fibers creating an internalcapacitive network throughout the leather fibers. Other cent and such asfrom aldehyde phenols and naphthalene ESD may be utilized as that of thegluteraldehyde solution and a preferred embodiment that gluteraldehydesolution utilized in the process may beat be between one and 7%, andeven more preferred range between two and 5% and even more preferred a3%. The water component can be preferably between 25%400%, between about20 in 80° Celsius; more preferably between 50% in 200% water between 40and 60° C. and even more preferably 100% water between 50° C. carbonblack powder can be mixed in different concentrations down to as littleas 10% depending upon the degree of capacitive nature required and aphysical appearance in color required. Preferably the carbon black isbetween one and 25% even more preferably between 10 and 25% and evenmore preferably at about 20%. The amount of carbon black powder utilizedvaries depending upon the physical characteristics of the skins beingre-tanned and the primary tanning process utilized. It is important tonote that the proper amount of carbon black be used in the processing ofthe re-tanning. If not enough carbon black is used in the process, thefunctionality of the leather will not occur. Where a suitable amount ofthe carbon black as utilized the full benefits of the capacitive networkthroughout the leather skins are achieved. Thus even though the leatherexhibits the surface characteristics of traditional black leather, theleather will allow a capacitive coupling a multi touch capacitive touchscreen. The times indicated for the drumming of the carbon black andGlutaraldehyde an additional drumming of the calcium formate arepreferred values and greater or lesser times may be utilized thefollowing ranges for the drumming of the leather.

1. An electrically-conductive modified material comprising: a leather orleather-like material, wherein the leather or leather-like materialcomprises a plurality of voids therewithin; an electrically conductiveagent; and a binder material; wherein at least a portion of the leatheror leather-like material is impregnated within the plurality of voidswith the electrically conductive agent and the binder at a sufficientconcentration to provide electrical conductivity in the modifiedmaterial.
 2. The electrically-conductive modified material of claim 1,wherein the modified material comprises at least about 30% electricallyconductive agent.
 3. The electrically-conductive modified material ofclaim 1, wherein the electrically conductive agent is selected from thegroup consisting of: carbon black, carbon nanotubes, graphite, PEDOT,silver, copper, gold, nickel, aluminum, indium, zinc, tin, andcombinations thereof.
 4. The electrically-conductive modified materialof claim 1, wherein the electrically conductive agent is substantiallyhomogenously dispersed or suspended within the binder material.
 5. Theelectrically-conductive modified material of claim 1, wherein theelectrically conductive agent is cured into the modified material. 6.The electrically-conductive modified material of claim 1, wherein themodified material has a volume resistivity of less than about 1.0×10⁶ohm-cm.
 7. The electrically-conductive modified material of claim 6,wherein the modified material retains a volume resistivity of less thanabout 1.0×10⁵ ohm-cm after the modified material is in its finishedform.
 8. The electrically-conductive modified material of claim 1,wherein the modified material further comprises a base coat, a colorcoat, a midcoat, and/or a finishing coat.
 9. The electrically-conductivemodified material of claim 1, wherein the modified material furthercomprises aqueous polyether polyurethanes, solvent-bornepolyether/polyester, aqueous acrylics, styrene butadiene rubber,nitrocellulose lacquers and water emulsions, cellulose acetate butyratelacquers and water emulsions, shellac, epoxy, polyvinyl chloride, oils,waxes, silicones, and/or combinations thereof.
 10. Theelectrically-conductive material of claim 1, wherein the electricallyconductive agent is loaded onto a plurality of fibers disposed withinthe leather or leather-like material.
 11. The electrically-conductivemodified material of claim 10, wherein at least some of the plurality offibers in the leather or leather-like material comprise a fiber chain.12. The electrically-conductive modified material of claim 11, whereinthe at least some of the plurality of fibers comprising the fiber chainoverlap in such a manner that the modified material can withstandtensile, compressive, or shear strains without suffering significantloss of the electrical conductivity in the modified material.
 13. Theelectrically-conductive modified material of claim 11, wherein the fiberchain has a length of at least 100 nanometers.
 14. A method formodifying a leather or leather-like material to beelectrically-conductive, the method comprising: providing a leather orleather-like material, wherein the leather or leather-like materialcomprises a plurality of voids therewithin; and providing anelectrically conductive material in at least a portion of the pluralityof voids within the leather or leather-like material at a sufficientconcentration to provide electrical conductivity in the modified leatheror leather-like material.
 15. The method of claim 14, wherein themodified leather or leather-like material has a volume resistivity ofless than about 1.0×10⁶ ohm-cm.
 16. The method of claim 15, wherein themodified leather or leather-like material retains a volume resistivityof less than about 1.0×10⁵ ohm-cm after the modified leather orleather-like material is in its finished form.
 17. The method of claim14, wherein at least some of the electrically conductive materialcomprises a fiber chain.
 18. The method of claim 17, wherein the atleast some of the electrically conductive material comprising the fiberchain overlaps in such a manner that the modified leather orleather-like material can withstand tensile, compressive, or shearstrains without suffering significant loss of the electricalconductivity in the modified leather or leather-like material.
 19. Themethod of claim 17, wherein the fiber chain has a length of at least 100nanometers.
 20. An electrically conductive modified leather orleather-like material prepared by a process comprising the steps of:providing a leather or leather-like material, wherein the leather orleather-like material comprises a plurality of voids therewithin; andproviding an electrically conductive material in at least a portion ofthe plurality of voids within the leather or leather-like material at asufficient concentration to provide electrical conductivity in themodified leather or leather-like material.
 21. The electricallyconductive modified leather or leather-like material of claim 20,wherein the modified leather or leather-like material has a volumeresistivity of less than about 1.0×10⁶ ohm-cm.
 22. The electricallyconductive modified leather or leather-like material of claim 21,wherein the modified leather or leather-like material retains a volumeresistivity of less than about 1.0×10⁵ ohm-cm after the modified leatheror leather-like material is in its finished form.
 23. The electricallyconductive modified leather or leather-like material of claim 20,wherein at least some of the electrically conductive material comprisesa fiber chain.
 24. The electrically conductive modified leather orleather-like material of claim 23, wherein the at least some of theelectrically conductive material comprising the fiber chain overlaps insuch a manner that the modified leather or leather-like material canwithstand tensile, compressive, or shear strains without sufferingsignificant loss of the electrical conductivity in the modified leatheror leather-like material.
 25. The electrically conductive modifiedleather or leather-like material of claim 23, wherein the fiber chainhas a length of at least 100 nanometers.